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I haven’t been blogging much lately, actually I haven’t been blogging at all in the last 4 months. The reason behind is I have been putting all my efforts in a new project I started recently, which absorbed all my attention and spare time.

I am proud to announce that my project is now live and available to everyone for download.

The project name is ExtendedTSQLCollector and you can find it at http://extendedtsqlcollector.codeplex.com. As you may have already guessed, it’s a bridge between two technologies that were not meant to work together, that could instead bring great advantages when combined: Extended Events and Data Collector.

ExtendedTSQLCollector is a set of two Collector Types built to overcome some of the limitations found in the built-in collector types and extend their functionality to include the ability to collect data from XE sessions.

The first Collector Type is the “Extended T-SQL Query” collector type, which was my initial goal when I started the project. If you have had the chance to play with the built-in “Generic T-SQL Query” collector type, you may have noticed that not all datatypes are supported. For instance, it’s impossible to collect data from XML or varchar(max) columns. This is due to the intermediate format used by this collector type: the SSIS raw files.

The “Extended T-SQL Query” collector type uses a different intermediate format, which allows collecting data of any data type. This is particularly useful, because SQL Server exposes lots of information in XML format (just think of the execution plans!) and you no longer need to code custom SSIS packages to collect that data.

The second Collector Type is the “Extended XE Reader” collector type, which takes advantage of the Extended Events streaming APIs to collect data from an Extended Events session, without the need to specify additional targets such as .xel files or ring buffers. This means no file system bloat due to .xel rollover files and no memory consumption for additional ring buffers: all the events are read directly from the session and processed in near real-time.

In addition to the filter predicates defined in the XE session, you can add more filter predicates on the data to collect and upload to the MDW and decide which columns (fields and actions) to collect. The collector will take care of creating the target table in your MDW database and upload all the data that satisfies the filter predicates.

The near real-time behavior of this collector type allowed me to include an additional feature to the mix: the ability to fire alerts in response to Extended Events. The current release (1.5) allows firing email alerts when the events are captured, with additional filter predicates and the ability to include event fields and actions in the email body. You can find more information on XE alerts in the documentation.

Here is an example of the email alerts generated by the XEReader collector type for the blocked_process event:

Another part of the project is the CollectionSet Manager, a GUI to install the collector types to the target servers and configure collection sets and collection items. I think that one of the reasons why the Data Collector is very underutilized by DBAs is the lack of a Graphical UI. Besides the features specific to the ExtendedTSQLCollector, such as installing the collector type, this small utility aims at providing the features missing in the SSMS Data Collector UI. This part of the project is still at an early stage, but I am planning to release it in the next few months.

My journey through the ins and outs of the Data Collector allowed me to understand deeply how it works and how to set it up and troubleshoot it. Now I am planning to start a blog series on this topic, from the basics to the advanced features. Stay tuned 🙂